ABSTRACT
Ascorbic acid, a unique chemical entity that functions both as an essential nutrient and as an active reducing agent, commands an important role in the metabolism and detoxification of many endogenous and foreign compounds. The ever-increasing volume of published research concerning ascorbic acid and drug biotransformation attests to the vitamin's central involvement in the organismal response to pharmacologic agents. Much of this work has focused on the role of ascorbic acid in maintaining normal rates of drug metabolism in species that require a dietary source of this vitamin, studied most commonly in the vitamin C-deficient guinea pig. Other investigators have demonstrated that many drugs which induce the mixed-function oxidase system also, in ascorbate-synthesizing species, accelerate the rate of ascorbate biosynthesis. Yet another line of investigation has been study of the protection that vitamin C affords against the toxicities of a wide variety of biologically active chemicals, including drugs. This review focuses on these areas of inquiry into the interaction between ascorbic acid and drugs, after first examining important methodological considerations in the design of drug-ascorbic acid studies.
